Ecosystems

Higher: Natural Divisions

While it might be tempting to use the terms 'ecosystem' and 'plant community' interchangeable, there is an important distinction! Ecosystems include plant communities but also include the abiotic aspects. Plant communities typically refer to only the biotic aspects of the plant kingdom present in an ecosystem.

Further, ecosystems can occur on many different scales, which kind of makes them an outlier from the hierarchical system we have been working from. Depending on the questions we want to ask about an ecosystem, we can view the entirety of Lake Michigan as an ecosystem. We can also view a temporary pool of water formed in a ditch as an ecosystem. Instead of being a measure of scale or of unique characteristics, the ecosystem concept allows us to look at the intertwined flow of energy and nutrients between biotic and abiotic factors of an ecosystem.

The four primary ecosystem types:

• Terrestrial – land-based ecosystems
  • forests
  • grasslands
  • deserts
  • tundras
  • coastal regions
• Lentic – aquatic ecosystems whose waters are typically still bodies of fresh water which rely on photosynthesis of algae and underwater plants to produce energy to thrive. These ecosystems range in size from very small, potentially temporary standing pools of water, to larger lakes:
  • ponds
  • marshes
  • lagoon
  • ditches
  • lakes
  • swamps
  • bogs
• Lotic – aquatic ecosystems that are characterized by flowing waters. These waters flow into other bodies of water and eventually end up in the ocean. Lotic ecosystems do not rely primarily on photosynthesis for their thriving. Their oxygen levels tend to be higher due to the continually moving current. Waters also tend to be clearer as photosynthesizing algae have less opportunity to proliferate. They include:
  • springs
  • brooks
  • rivers
  • streams
  • estuaries
• Artificial – some believe it's important to distinguish human-made (artificial) ecosystems from 'natural' ecosystems. Since humans are a part of nature, the line blurs for me a bit, especially since humans have evolved alongside and shaped their ecosystems (for better or worse) for as long as we've been around. Perhaps the important distinction here is that artificial ecosystems may include technology (air pump in an aquarium) and has food chains and nutrient cycles that tend to be incomplete, requiring human intervention to close the loop. Examples of what some might call 'artificial' ecosystems include:
  • Terrariums
  • Biodomes
  • Aquariums
  • Agricultural Fields
  • etc.

Lower: Plant Communities